PROJECT SUMMARY The primary objective of the proposed course is to provide an in-depth and modern tutorial on the organization, structure, and function of the visual system. In the past three iterations of the course, renewed focus has been placed on diseases of the visual system and the development and implementation of novel techniques and approaches to study the structure and function of the visual system ? both on a cellular and systems level. The course format continues to evolve after >25 years in order to deliver the most comprehensive and impactful training in vision science to the students and to encourage students to develop their own framework for thinking about vision. Days are organized into thematic topics (e.g. color vision, motion detection throughout the visual system) in which two world-renowned experts provide the students: 1) a comprehensive overview of the subfield including historical perspective; 2) descriptions of current understanding of progress in the subfield, critical issues, and novel methods in use; 3) presentations of cutting edge, often unpublished, research within the subfield; and 4) ample opportunities for interaction with instructors to share ideas and receive feedback on students' own research. Instructors are chosen on the basis of their longstanding and/or particularly significant contributions to the field. Each instructor provides in-depth expertise in a specific area that complements the others and the instructors are ?clustered? along themes or topics over 1-2 day spans to encourage thorough coverage of a subfield, controversies and all. Teaching ability and willingness to interact with students is also a serious consideration when inviting instructors. The trainees (~22-25) are chosen by the course directors from a large pool of applicants. This course provides an unusual opportunity for scientists already in vision science to deepen their knowledge and formulate plans for their work and for those new to the system to get up to speed on the history, models, and modern techniques and understanding in vision science. Students of the course gain an unparalleled foundation of knowledge above and beyond anything offered in a typical graduate school course. But perhaps more importantly for their future careers, students define their framework for studying the visual system, often embarking on new lines of inquiry and/or collaborations following their course experience. Evidence for success of the Vision Course lies in the large percentage of students who go on to run their own independent laboratories. The course has consistently made, and will continue to make, efforts to include a diverse group of participants, being particularly mindful of the inclusion of women, US minorities and a good balance of national and international students and instructors.